%I A001869 M3860 N1582
%S A001869 1,5,15,45,165,629,2635,11165,48915,217045,976887,4438925,20346485,
%T A001869 93900245,435970995,2034505661,9536767665,44878791365,211927736135,
%U A001869 1003867701485,4768372070757,22706531350485,108372083629275,518301258916445
%N A001869 Number of n-bead necklaces with 5 colors.
%D A001869 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001869 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001869 E. N. Gilbert and J. Riordan, Symmetry types of periodic sequences, Illinois 
               J. Math., 5 (1961), 657-665.
%D A001869 J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 
               162.
%D A001869 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see 
               Problem 7.112(a).
%H A001869 T. D. Noe, <a href="b001869.txt">Table of n, a(n) for n=0..200</a>
%H A001869 <a href="Sindx_Ne.html#necklaces">Index entries for sequences related 
               to necklaces</a>
%H A001869 INRIA Algorithms Project, <a href="http://algo.inria.fr/bin/encyclopedia?Search=ECSnb&argsearch=5">
               Encyclopedia of Combinatorial Structures 5</a>
%H A001869 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Necklace.html">Link to a section of The World of Mathematics.</a>
%F A001869 (1/n)*Sum_{d|n} phi(d)*4^(n/d), n>0.
%Y A001869 Sequence in context: A084244 A099235 A035069 this_sequence A058425 A079798 
               A037504
%Y A001869 Adjacent sequences: A001866 A001867 A001868 this_sequence A001870 A001871 
               A001872
%K A001869 nonn,easy
%O A001869 0,2
%A A001869 N. J. A. Sloane (njas(AT)research.att.com).